Do you want to know how much it will cost to build an NFT Marketplace like OpenSea? There are many factors that affect the price of developing an NFT Marketplace like OpenSea, so we can't provide an exact estimate.
Development of this factor depends on your specific requirements, such as the type of features you want to implement, the complexity of the project, the theme and design you choose, and the developer you hire.
If you like to know the approximate cost of developing such an NFT Marketplace, you can arrange the funds yourself at the time of the development. The cost to create an NFT Marketplace like OpenSea ranges from $10k to $50k.